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CMS Results (non-Higgs)

Miami 2013. CMS Results (non-Higgs). Jorge L. Rodriguez T he CMS Collaboration Florida International University December 14, 2013. The LHC and CMS. 78 vertices! during special high pileup run. In 2012 <N PU >  23. CMS Public Results. http://cms.web.cern.ch/org/physics-papers-timeline.

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CMS Results (non-Higgs)

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  1. Miami 2013 CMS Results (non-Higgs) Jorge L. Rodriguez The CMS Collaboration Florida International University December 14, 2013

  2. The LHC and CMS 78 vertices! during special high pileup run. In 2012 <NPU>  23 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  3. CMS Public Results http://cms.web.cern.ch/org/physics-papers-timeline • CMS has published more than 270 papers since startup • Electroweak, Top, B physics, SM ~ 80 • Exotica Searches ~ 66 • SUSY Searches ~ 35 • Higgs ~ 25 • Heavy-Ion Physics ~ 23 • Many more papers are in the pipeline Impossible to show all important results in 30 minutes so I will highlight a few of the newer results that are public with the full 8 TeV data Outline: Standard Model Results SUSY Model Exotica https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResults Miami 2013 Conference: Ft. Lauderdale, December 12-18

  4. Standard Model Physics Inclusive Cross Sections @ 7 and 8 TeV Triple/quadruple Gauge Couplings Top Physics Rare B decays

  5. Inclusive Z/W Cross Sections @ 8 TeV SMP-12-011 • Precision measurements are important tests of SM physics • Inclusive W/Z production cross sections @ 8 TeV with 18.7/pb • Dedicated low pileup run & triggers • WX channel: look for prompt energetic and isolated lepton with significant MET • ZX channel: look for two energetic and isolated leptons • Results presented as ratio • Total uncertainties ~ 3.8% • systematic and some theoretical errors cancel Miami 2013 Conference: Ft. Lauderdale, December 12-18

  6. Inclusive Z/W Cross Sections @ 8 TeV SMP-12-011 • Results on cross-section times BF • The measured and predicted W vs. Z production cross section (~ 1.5 sigma discrepancy) B B Miami 2013 Conference: Ft. Lauderdale, December 12-18

  7. SM: anomalous TGC & QGC Triple (Quadruple) Gauge Couplings • CMS reports limits on of these parameters with data collected at 7 & 8 TeV • From analysis on production of with 5/fb @ 7 TeV • Final states: • Limits at 95% CL on aTGC parameters for the (worlds best on ) EWK-11-009 • Triple/Quadrupole gauge couplings provide important tests of EWK sector, deviation from SM expectations could point to NP • AnLeff is written in terms of parameters related to SM couplings “LEP parameterization” • For the self interaction terms we used and (= 0 SM) • Similarly for where in SM, to 1-loop CP even Miami 2013 Conference: Ft. Lauderdale, December 12-18

  8. Summary of CMS aTGC Results https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsSMPaTGC ZZ EWK-11-009 SMP-13-005 SMP-12-020 SMP-12-015 SMP-12-005 EWK-11-009 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  9. CMS aQGC Results https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsSMPaTGC Studies of exclusive two-photon production of pp collisions @ 7 TeV FWD-12-010 SMP-13-009 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  10. SM: Top Quark Physics • Top mass Measurements • Top mass (Yukawa coupling) one of the 19 SM parameters, a critical element in SM calculations, constraints on Higgs mass and used to investigate internal consistency of SM • CMS’ new top mass is: (Lint = 20/fb with 2010 - 2012 data) 1stStnd analysis: dileptons, leptons+jets 2010 + dileptons, leptons+jets & all-jets 2011 (5 channels) 2nd 5 channels in Standard + 2 additional “Alt. analysis” Measurement updates CMS combination results • CMS 2013 combined result with with up to 19.6/fb (2010-2012) TOP-13-002 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  11. SM: Top Quark Polarization TOP-13-001 • Top quark polarization with 19.7/fb @ 8 TeV • Short decay time: decay products retain spin orientation of the fundamental original quark • Excellent opportunity to probe for NP by a comparison to precise SM predictions • In t-channel top quarks ~100% polarized via V-A coupling • Event selection & Analysis • Single top production: one lepton, one b-jet + MET • MLA on the shape of the BDT discriminant • Results • Unfolded distribution • Agreement with SM expectation Assuming=1 channel channel Miami 2013 Conference: Ft. Lauderdale, December 12-18

  12. SM: Top Quark Physics • New combined CMS/ATLAS results for • All 3 stnd CMS plus 2 ATLAS (dileptons + leptons+jets) • Use Best Linear Unbiased Estimate “BLUE” method • Correlations in systematic taken into account in the combination • CMS/ATLAS combination on top cross section @ 7TeV: @ 7 TeV TOP-13-005 • 28 new CMS TOP results in 2013 • TOP-13-010: Ratio of top decays to b-jets/jets • TOP-13-08 : W boson helicity in top decays • TOP-12-33 : asymmetry @ 8TeV Miami 2013 Conference: Ft. Lauderdale, December 12-18

  13. A Summary of CMS SM Cross-Section https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsCombined Miami 2013 Conference: Ft. Lauderdale, December 12-18

  14. SM: • Large cross section at the LHC allows us to measure rare decays of the B and Bs meson • Time integrated branching fractions in SM are small: • B • Simultaneous search for using 5/fb @ 7 TeV & 20/fb @ 8 TeV • Search for dimuons with • Normalize to to minimize uncertainty in prod x-section • BTDs method is used to extract the number B meson decays • 12 BDT regions defined, are used each with 12 variables: kinematics, tracking, impact & flight length significance, 4 muon isolation variable… • Main bkgsemil-leptonic B combinatorics, modeled in mass sidebands, MC used to model (d) (d) BPH-13-004 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  15. SM: Other B Measurements BPH-13-004 https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsBPH13004 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  16. SUSY

  17. SUSY Search Strategies • Searches can be categorized by n-leptons in FS • 0 leptons – fully hadronic modes • 1 lepton, 2 leptons (OS/SS), multileptons • di photon modes, photon + leptons • Most include n-jets and all include MET • Simplified Model Spectrum (15 topologies) • Focus on a specific decay chains with cross-sections parameterized in terms of SUSY particle masses and assume SUSY BF under study are 100% • Limits on for specified topologies presented as reference in which to place limits on different theoretical models • I show only a subset of the ≥ 0 leptonic analyses that correspond to 5 different topologies in the RPC modes • Searches gluino mediated sbottom & stop production: (T1bbbb & T1tttt): 0-leptons • Search for stop production into single lepton final state: (T2tt & T2bW): 1-lepton • Search for EW production of chargino/neutralino production in final states with Higgs: (TChiWH): 1-lepton, dilepton(SS), ≥ 3 leptons • And then summarize SUSY mass limits obtained through many other analysis extracted from the full dataset at @ 8 TeV Miami 2013 Conference: Ft. Lauderdale, December 12-18

  18. SUSY: Gluino production T1tttt & T1bbb SUS-12-024 • Final states: ≥ 3 jets with ≥ 1 b-tagged jet + MET • T1bbbb: • T1tttt: • Event selection: data divided into 176 exclusive bins • (ZL) Signal sample: no isolated or ID’d leptons • (SL) Control: require a single isolated, ID’d lepton • (LDP) Control: angle btw MET vector and pt of highest jet, selects QCD events • (Zee,Z) Control: Events selected from dileptons Z decays • Backgrounds: • Dominant bkg from • W+jets, Z+jets and QCD • Analysis • Perform a global likelihood fit in three simultaneous variables, MET, HT and number of bjets to 165 exclusive bins. • Results: No excess over SM predictions Miami 2013 Conference: Ft. Lauderdale, December 12-18

  19. SUSY: T1tttt, T1bbbb Interpretation contours SUS-12-024 • Contour plot shows limits on gluino production cross section in the gluino and neutralino mass parameter space at the 95% C.L. with 19.4 pb-1 @ 8 TeV • We use SMS assumption i.e., 100% BR for gluino to top/bottom squark + LSP • Limits on gluino mass up to 1.2 TeV (LSP mass = 0) at the 95% C.L Miami 2013 Conference: Ft. Lauderdale, December 12-18

  20. SUSY: Gluino Mass Exclusion Summary • Summary of other public CMS analysis exclude gluino mass up to 1.3 TeV with • Gluino production to tops, to bottom mesons and to quarks compared to expectations SUS-12-024 SUS-12-028 SUS-13-004 SUS-13-007 SUS-12-026 SUS-13-008 SUS-13-013 SUS-13-016 SUS-12-024 SUS-12-028 SUS-13-004 SUS-12-028 SUS-13-012 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  21. SUSY: Stop pair production T2tt, T2bW SUS-13-011 • Final states: 1 lepton + jets (b-tagged) + MET • T2tt: • T2bb: • Event Selection: • Single isolated high pT (e or ) • Njets4 with at least one a b-tagged jet • MET>100 GeV and MT>120 GeV… • Analysis: Boosted Decision Trees • Utilize multi-signal regions in parameter space • Each BDT employs relevant kinematic variables, MET, … that correspond to region • Cut based cross-check • Backgrounds: • Dominant SM: dilepton top pairs, (thad)(tlep)& W+jets • Results: No excess beyond SM predictions Miami 2013 Conference: Ft. Lauderdale, December 12-18

  22. SUSY: T2tt, T2bW Interpretation contours SUS-13-011 T2tt mode T2bW mode: B=100% SUS-13-011 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  23. SUSY: Stop Mass Exclusion Summary • Summary of other public CMS analysis exclude up to 710 GeV with @ 95 C.L. • Gluino production to tops, to bottom mesons and to quarks compared to expectations • Another cut & count analysis as an additional xcheck • Exclusion limits are slightly worse but consistent SUS-13-011 SUS-13-004 SUS-13-015 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  24. SUSY: EWkino production TChiHW Utilize mH constraints • TChiHW: Dominant if are wino like, is bino-like and • Event selection for three channels • : exactly 1 lepton & 2-btagged jets, + MET • : SS dileptons + jets + MET • multi-leptons + MET • Analysis • Define 4 signal regions in MET form and count events between100 to 150 GeV around mass of the Higgs. • Additional requirements on lepton , MT .. form and count events below 120 GeV • Multiple signal regions formed that categories the number and types of leptons, MET, whether there as SS or SF leptons … The yields are then compared with background estimates • Results: • All three channels combined to improve sensitivity • No excess over SM predictions SUS-13-017 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  25. SUSY: EWkino production Results SUS-13-017 We report limits on production cross section as a function of mass assuming equal masses vs mass of at the 95% C.L. with 19.5 pb-1 @ 8 TeV For masses of the LSP below 25 we exclude mass of the < 204 GeV Miami 2013 Conference: Ft. Lauderdale, December 12-18

  26. SUSY: EWKino Mass Summary • Exclusion limits for EWK’ino assuming equal masses, in the SMS with 19.5 fb-1 of data collected at 8 TeV • We exclude masses up to 740 GeV depending on mass of LSP and decay mode SUS-13-006 SUS-13-017 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  27. SUSY Exclusion Summary R-parity violating models R-parity conserving models Miami 2013 Conference: Ft. Lauderdale, December 12-18

  28. Exotica Searches

  29. Exotica Search Strategies • A rather large number of BSM theories • CMS has almost 40 new Exotica and Beyond the 2nd generation (B2G) analyses on 2012 data • Difficult to organize analyses I am not the first to notice… • I will summarize our latest results on: • Dileptons searches • Search for resonances that decay to Vector Bosons • Search for vector-like T2/3 quark (B2G) • Heavy Stable Charged Particles Miami 2013 Conference: Ft. Lauderdale, December 12-18

  30. Exotica: Di leptons SUS-12-061 • Many BSMs predict narrow resonances at TeV scale • GUT models, SUSY, Extra dimensions, … • Easy to spot at LHC, more important than L • Signature: • : look for OSSF dileptons() • Challenge: very stiff tracks degrades momentum resolution especially in the channel. @ 1 TeV ~15% • Event selection • High pt, isolated, ID’d, back to back leptons (from primary vertex • Backgrounds • Dominant DY backgrounds to less dominant miss ID’d jets • Modeled by MC (NNLO) or data when possible • Analysis & Results • Relative fractions of simulated bkgs are fixed by theoretical cross sections with overall normalization set to data in • Results: invariant mass spectra agrees with SM Miami 2013 Conference: Ft. Lauderdale, December 12-18

  31. Exotica: Di leptons Interpretation Muons and all electrons, BB+ BE • Limits on Z’ mass are: With 20/fb of data @ 8 TeV we set limits at the 95 % C.L. on the ratio The likelihood functions for the signal and background shapes and use the narrow width approximation about 40% off the nominal predicted resonance mass for aand use ± 30 GeV for peak Miami 2013 Conference: Ft. Lauderdale, December 12-18

  32. Exotica: Di Boson Resonance EXO-12-022 EXO-12-021 • Many BSMs predict heavy resonances that can couple to SM vector bosons • Gravitons in RS models with warped extra dimension that decays to SM fermions but are suppressed w.r.t decays to VB • We search for: • : 2 OSSF leptons1 “fat” jet • : exactly 1 lepton, 1 “fat” jet + MET • Event selection • Isolated ID’d leptons () and PF jets • One VB is reconstructed in leptonic mode the other hadronic • For resonances M > 600 GeV the quarks from the W/Z are merged into a single jet • Use jet substructure techniques to refine the merged jets • Jet pruning: remove soft jet components improves jet mass resolution • Construct N-subjettiness), allows dipole jets structure to discriminate between merged jets from regular QCD jets • Analysis: • Signal characterized as a bump in VV invariant mass spectrum • Results: • Both and invariant mass spectra agree with SM expectations Miami 2013 Conference: Ft. Lauderdale, December 12-18

  33. Exotica: Di Boson Resonance EXO-12-022 EXO-12-021 • Many BSMs predict heavy resonances that can couple to SM vector bosons • Gravitons in RS models with warped extra dimension that decays to SM fermions but are suppressed w.r.t decays to VB • We search for: • : 2 OSSF leptons1 “fat” jet • : exactly 1 lepton, 1 “fat” jet + MET • Event selection • Isolated ID’d leptons () and PF jets • One VB is reconstructed in leptonic mode the other hadronic • For resonances M > 600 GeV the quarks from the W/Z are merged into a single jet • Use jet substructure techniques to refine the merged jets • Jet pruning: remove soft jet components improves jet mass resolution • Construct N-subjettiness), allows dipole jets structure to discriminate between merged jets from regular QCD jets • Analysis: • Signal characterized as a bump in VV invariant mass spectrum • Results: • Both and invariant mass spectra agree with SM expectations Miami 2013 Conference: Ft. Lauderdale, December 12-18

  34. Exotica: Di Boson Resonance • Set upper limit @ 95 C.L. on B as a function of the with 2012 data • Lower mass bound the on Bulk Graviton TeV for the ZZ mode with similar result from the WW mode EXO-12-021 EXO-12-022 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  35. B2G: Inclusive Search for Vector-like T2/3 EXO-12-015 • A non-SM 4th generation or massive partner to top quark • Can enhance CP violation, heavy could be a DM candidate, could help stabilize Higgs mass in absence of MSSM • Vector-like T predicted in Little Higgs models and in warped extra dimensions • Inclusive search for: • BF 0.50, 0.25, 0.25 : leptons + jets (bjets) (W-jets) • Event selection • Single lepton channel: 1 Isolated high pt lepton () + ≥ 3 jets with 1 W-jet or 4th jet pT>35 GeV • Multi-lepton channel: exactly 2 or 3 (SS/OS) leptons with n-jets/b-jets consistent with topology • Use jet substructure techniques used to refine the merged jets “W-jets” • Analysis: • Single lepton + jets uses a BDT (max sensitivity) • Multi-lepton (2 or 3 leptons) 12 cut & count categories OS, SS … • All channels combined in limits. • Results: no excess observed over SM expectations Miami 2013 Conference: Ft. Lauderdale, December 12-18

  36. B2G: Inclusive Search for Vector-like T2/3 EXO-12-015 • Set upper limit @ 95 C.L. on B as a function of the assuming B = 0.5, 0.25, 0.25 with 19.6 pb-1 @ 8 TeV • Lower mass limits @ 95 C.L. between 687 and 782 GeV for all possible BF of the T to the three decay modes considered Miami 2013 Conference: Ft. Lauderdale, December 12-18

  37. Exotica: Long Lived Particles S. Worm @ SEARCH 2013 • Many extension of SM predict heavy long lived (stable) charged particle HSCP • Ex:in GMSB, with LSP = gravitino, NLSP = L.L. gluino/stop/stau • A colored NLSP can form an R-hadron, lead to interesting events • Signature • Candidates with dE/dx losses ≠ MIP • Candidates with large Time-of-Flight w.r.t. IP • Analysis: • Variables: • is the energy loss dE/dx as measured with the Silicon Tracker • a S.C.vM uses dE/dx & compares with MIP • 1/buses Muon sys’s timing info w.r.t. IP • pT the transverse momentum • Five different analysis strategies employed • Use an ABCD method to separate signal from background • HSCPs with |Q| < 1e: tracker only is used. Here we use pTand select tracks with dE/dx less than expected for |Q| = 1e. • HSCPs with |Q| > 1e: tracker + Muon use pT, dE/dx and TOF optimized for large dE/dx than expected for |Q| = 1e • HSCPs with |Q| = 1e: 3 analyses that either use tracker or the muon system alone, or both systems together. For these analyses the track pT ,theIas and/or TOF is used to discriminate btw bkg and signal • Results: No excess observed over SM EXO-12-026 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  38. Exotica: Long Lived Particles, limits on n charged particles EXO-12-026 • No significant excess observed over SM predictions in full Run I data • Set upper limits on cross section vs. mass for models where gluinos, stops or staus are produced • Lower mass limits on gluino with particular R-hadron model assumptions are made as well as exclude masses for HSCP with |Q| ± 1e as shown. Miami 2013 Conference: Ft. Lauderdale, December 12-18

  39. CMS Exotica 95% CL Exclusion Limits Miami 2013 Conference: Ft. Lauderdale, December 12-18

  40. Summary • The LHC’s pp @ 8 TeV RUN I ended at the end of 2012 • CMS recorded more than 23 fb-1 of data @ 8 TeV • As well as 6 fb-1 @ 7 TeV in 2010 and 2011 • Standard Model measurements • More data and some improvements in systematics => more precise tests of SM • Turning towards rarer processes, rare B decays, diboson production, T(Q)GC… • Many new measurements TOP physics • In general measurements consistent with SM but results are challenging NLO and NNLO predictions • SUSY, Exotica and Beyond the 2nd Generation • Searches for New Physics in SUSY and model BSM continue to push forward with no evidence so far for BSM physics • Under the SMS we place limits on SUSY masses up to the 0.2 to 1.3 TeV excluding a significant, but not all, portion of SUSY parameter space particularly cMSSM. Natural SUSY is being stressed • Eagerly awaiting Run II at 13-14 TeV with Lint= 1.0 ± 1034cm-2s-1 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  41. SUperSYmmetry SUSY’s LSP a Dark Matter candidate A “natural” solution to the Weak Scale hierarchy problem Coupling constant GUT fixer Miami 2013 Conference: Ft. Lauderdale, December 12-18

  42. SUSY Challenges SUSY spectra quite complicated and model dependent At the LHC SUSY cross sections are tiny wrt to SM Miami 2013 Conference: Ft. Lauderdale, December 12-18

  43. Analysis Generalities • Triggers L1 + HLT • Many different triggers used for the analysis discussed • Typically close to 100% efficient • Monte Carlos • Various generators used Pythia6/8, HERWIG6/++, SHERPA • Matrix Element calculators: Alpgen MadGraph, NCatNLO… • GEANT4: full simulation of particle interaction and digitization • FASTSIM: paramerized simulation of particle interactions • Event selection • Tracks: general requirement on pT, PV (, |h| • Jets: • JetEnergyCorrections applied to all jets they include correction for pileup (IT, EOOT, LOOT), mismeaurement • Various Jet clustering algorithms used, anti-kT… with some cuts jet cone • b quarks: b-tags jets typically use the CSVM algorithm to tag the jets a bjet (b-tagged jet) • Particle Flow (PF) is used throughout • Assigns objects to types of events, photons, electrons, charged & neutral hadronic jets, muons • Backgrounds • Data driven control samples used where possible, sidebands, tag-probe, etc. • Monte Carlos used extensively but corrected by comparing to data Miami 2013 Conference: Ft. Lauderdale, December 12-18

  44. SUSY Strategies • Some of the more variables used through out • = • = • Other variables such Razor, • SUSY Analyses employ missing momentum/energy transverse mass, and other variables that discriminate between backgrounds and signal when signal usually have one or more invisible particles in the final state Miami 2013 Conference: Ft. Lauderdale, December 12-18

  45. Exotica: Di Boson Resonance EXO-12-022 EXO-12-021 • Many BSMs predict heavy resonances that can couple to SM vector bosons • Gravitons in RS models with warped extra dimension that decays to SM fermions but are suppressed w.r.t decays to VB • We search for: • : 2 OSSF leptons1 “fat” jet • : exactly 1 lepton, 1 “fat” jet + MET • Event selection • Isolated ID’d leptons () and PF jets • One VB is reconstructed in leptonic mode the other hadronic • For resonances > 600 GeV the quarks from the hadronic VB are merged into a single jet • Use jet substructure techniques to refine the merged jets • Jet pruning: remove soft jet components improves jet mass resolution • Construct N-subjettiness), allows dipole jets structure to discriminate between merged jets from regular QCD jets • Analysis: • Signal characterized as a bump in VV invariant mass spectrum • Results: Both and invariant mass spectra agree with SM expectations High Purity (1JHP) Low Purity (1JLP) Miami 2013 Conference: Ft. Lauderdale, December 12-18

  46. Exotica: Long Lived Particles Results The mass is computed from The No. of tracks for the three analyses searching for HSCP with charge = 1e The No. of tracks in the search for fractionally charged HSCP (Tracker only) The No. of tracks in the search for multi charged HSCP (Traker + TOF) EXO-12-026 Miami 2013 Conference: Ft. Lauderdale, December 12-18

  47. SUSY: Other Squark Mass Summary • Exclusion limits for bottom squark and squark masses, in the SMS from 20 fb-1 of data collected at 8 TeV (2012) • We exclude squark masses up to 780 GeV depending on mass of LSP and decay mode SUS-13-002 SUS-13-008 SUS-13-013 Miami 2013 Conference: Ft. Lauderdale, December 12-18

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